Chemical Vapour Deposition (CVD) of wear resistant coatings on cemented carbide cutting tools has been an industrial practice for more than 30 years. Properties of coated inserts have been constantly improved during the years; life time and reliability in terms of resistance to edge fracture have been enhanced considerably. A noticeable improvement in performance of CVD-coated tool inserts came about when Ti(C,N) produced by the MTCVD (Moderate Temperature CVD)-technique begun to come into the tool industry about 10-15 years ago. An improvement in the toughness properties of the cutting tool insert was then obtained. Today the majority of tool producers use this technique. Today's modern tool coatings also include at least one layer of Al2O3 to achieve high wear resistance and to protect the carbide substrate from excessive heat during cutting.
EP1953258A1 discloses that a cutting tool provided with an α-alumina layer with a (001) texture, as measured by a strong (006) diffraction peak, results in an improved toughness and wear resistance of the cutting tool. The tendency for plastic deformation of the cutting edge was reduced.
WO2013/037997 discloses a cutting insert for turning in steel, comprising an α-Al2O3 layer with a (001) texture as measured by a strong (0 0 12) diffraction peak. The insert is subjected to a surface treatment of blasting to provide a specific stress state in the cutting insert.